CVE-2026-27169Network attack vector

Persistent XSS via unsafe chat HTML interpolation

Published Feb 20, 2026 · Updated Feb 20, 2026

Persistent XSS in OpenSift 1.1.2-alpha and earlier allows remote authenticated users to execute JavaScript in a victim's browser. The chat template inserts stored titles, previews, notes, and flashcard values through unsafe HTML rendering instead of DOM nodes and textContent. An attacker must influence stored study, quiz, or flashcard content and induce another authenticated user to view it, enabling actions in that user's local app session.

CVSS severity8.9
High
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Persistent XSS in OpenSift 1.1.2-alpha and earlier allows remote authenticated users to execute JavaScript in a victim's browser. The chat template inserts stored titles, previews, notes, and flashcard values through unsafe HTML rendering instead of DOM nodes and textContent. An attacker must influence stored study, quiz, or flashcard content and induce another authenticated user to view it, enabling actions in that user's local app session.

The record

CVE
CVE-2026-27169
Published
Feb 20, 2026
Updated
Feb 20, 2026
Vendor
OpenSift
Product
OpenSift
Classifications
CWE-79, CWE-116, T1189
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 20, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 20, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 1.1.3-alpha

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

OpenSift · OpenSiftversion=< 1.1.3-alpha

Published CVSS scores

8.9GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-116Improper Encoding or Escaping of Output
T1189Drive-by Compromise

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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